Switch



Patented May 15, 1928. v

UNITED STATES PATENT OFFICE.

CHRISTIAN AALBORG, OF PITTSBURGH, PENNSYLVANIA, ASSIGIWOR TO WESTIF'G- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION. 01 IENNSYL- VANIA.

SWITCH.

Application iuea July 31, 1924. Serial no. 129,222.

My invention relates to electric switches for use in portable electric dev1ces and particularly to switches adapted-for use in the handles of vacuum cleaners. 6 Heretofore, switches employed in vacuum cleaners have been of the single-break typeand an occasional short circuit of the break contacts energized the motor circuit.

An object of my invention is to provide 1 a switch for a vacuum cleaner, that will interrupt the energizing circuit in at least two points so that ashort circuit in one set of contacts will not energize the motor circuit.

Another object of my invention-is to provide a switch which is simple in construction, easy to manufacture and eflicient in operation.

The invention comprises a pair of contact springs secured on a block of insulation in p the handle of a vacuum cleaner and having a conducting pin interposed therebetween and embedded in a piece of insulation. The piece of insulation is secured to a plate havmg a semi-cylindrical cup portion with which an additional plate, also having a cup portion, cooperates to house a spring. Manually operable means are provided or moving the lower plate with respect to the upper plate whereby the spring is subjected to tension, and, after suflicient tension has been a plied, the upper plate will be impelled 1 contact.

In the drawings, N

Figure 1 is a longitudinal section through the upper end of the handle of a vacuum cleaner, showing the switch parts substan tially in top plan view. I

Fig. 2 is a vertical section through the handle, showing the hand grip partly in elevation and the switch parts partly in side,

elevation and partly in section.

Figs. 3, 4 and 5 are detail views of an up per plate.

lFigs. 6, 7 and 8 are detail views of a lower p ate.

Fig. 9 is a detail view of a push button. Fig. 10 is a longitudinal sectional view through the handle, similar to Fig. 1, illustrating a modification of the invention.

Fig. 11 is a crosssectional view on the line XI-XI- of Fig. 12, illustrating the modificationshown inFig. 10.

y the spring to make or break the Fig. 12 is a longitudinal sectional view taken on the line XII-XII of Fig. 11.

Figs. 13 and 14 are longitudinal sectional vlews, simllaryto Fig. 1, illustrating theswitch parts in successive positions of operation, and F1g. 15 is a diagrammatic View illustratmg the connections of the switch.

My invention is disclosed as applied to a vacuum cleaner handle of the type disclosed in a. copending application Serial No. 585,- 878, filed Sept. 2, 1922, entitled Vacuum sweeper but is of general a plication and is not limited to a device of tl i acter. I Referring to Figs. 1' and 2, the handle 1 1s cylindrical and is secured to a cylindrical extension 2 of a hand grip 3. A cylindrical block 4 of insulation is secured inthe han dle 1. A conductor 15, electrically connected to a motor 5a, extends through a channel in the block. 1 into a quadrantular recess 6, where it is secured to one arm' of a bracket 7 of U-shape. The bracket 7 is secured in position by a screw 8 extending'longitudinally through the block 4. The other arm of the bracket is secured to a contact spring 9.

' Another quadrantular recess 10 is provided below the recess 6 into which extends a conductor 11 that is electrically connected to a contact spring 12 in the manner in which, the conductor 5 is connected to the contact spring 9. The conductor 11, at its other end, is affixed to aplug 11a. A third conductor 13 extending from the motor 5a is connected to a third contact spring 14: and therebelow a fourth contact spring 14a and a. fourth conductor 13a shown only diagrammatically in Fig. 15 are positioned. The fourth conductor 13a extends from the fourth contact springl la to the plug 11a.

Contact springs 9 and 12 are bent at their ends to rest against the ends of a pin 15 embedded in an insulating block 16. A con- 1s specific chartact pin 17, carried by the insulating block rected flanges 23/ The anges receive 8. rectangular lower plate 24 having a cup 25 formed thereon.

The cups 20 and 25 cooperate to house a helical spring 26. The hand grip 3 is provided with openings slidably receiving a push button 27. The push button has a longitudinal slot 28 therein and a pin 30 projecting into the slot. The slot 28 receives the ends of the upper plate 18 and thelower plate 24, and the pin 30 is received in a slot 31 in the plate 24 extending at an acute angle with respect to the sides of the plate.

When the switch is on, the relations of the parts are as shown in Fig. 1, the pin 30 being adjacent to a corner of the projectiOn 22.

In the modification of the device shown in Figs. 10, 11 and 12, the handle 32 and the hand grip 33 are similar to those of the modification already described. There is no push button, however, but a collar 34 is provided instead. The hand grip 33 and the handle 32 are rigid with each other and are provided with a pair of registering segmental slots 35 through which projects a pin 36 rigid with the collar 34. The pin 36 is received in a slot'37 in a lower trough 38 formed on alower plate 39.

An upper plate 40 has an upper trough 41 with a projection 42 downwardly directed therefrom adjacent the pin 36. The troughs 38 and 41 are provided with four slots 42 disposed in a horizontal line and receiving a transverse pin 43 secured at its ends to the hand grip 33. The other switch parts of this modification are the same as those of the modification previously described.

In the modification illustrated in Figs. 1, 2, 13 and 14, the pin 30, when the switch is olosedis adjacent to that corner of the projection 22 which is to the left from the standpoint of the operator of the vacuum cleaner. When the push button 27 is urged manually to the right, the pin 30. causes the lower plate 24 to move rearwardly, that is, towards the hand grip 3 b reason of the inclination of the slot 31. he lower plate is guided in this movement by the flanges 23. The upper plate 18 during this phase of the operation 1s not permitted to move rearwardly as the pin 30 abuts against the projection 22. When the pin 30 passes beyond the rear righthand corner of the projection 22, the upper plate 18 is released and is urged rearwardly by the spring 26 which has been compressed by the movement of ush button 27.

The tendency of t e spring 26 is to urge the upper plate 18 rearwardly until the rear Wall of the inverted cup 20 is vertically alined with the rear wall of the cup 25. Fig. 14 illustrates the positions of the parts after the rearward movement of upper plate This rearward movement causes the insulating block 16 to move rearwardly and removes the contact pin 15 from contact springs 9 and 12. This breaks the circuit through the conductors 5 and 11. The con tact pin 17 is also removed from the contact spring 14 and the circuit through conductor 13, which is at a different potential from conductors 5 and 11, is likewise broken.

The insulating block 16 is then supported at one end by the contact springs and, at the other end, by the upper plate 18.

When it is desired to close the switch, the pushbutton 27 is moved towards the left to engage the projection 22-which is moved rearwardly until the pin 30 passes therebeyond and permits the spring 26 to urge the upper plate 18 forwardly a distance equal to that traveled by the lower plate 24 which is moved forwardly by the pin 30 moving in slot 31.

In the operation of the modification illustrated in Figs. 10, 11 and 12, the rotation of the collar 34 in a counter-clockwise direction, as regarded by an operator when the partsare in the position shown in Fig. 10, urges lower plate 39 rearwardly by reason of the lateral movement of the pin 36 in slots 35 and 37. The lower plate 39 is supported in its rearward movement by the pin 43 which permits sliding of the lower plate.

Rear-ward movement of the upper plate 40 is prevented during this phase of the operation by the engagement of the pin 36 with projection 42. After the pin 36 passes beyond the projection, the upper plate 40 is released and is urged rearwardly in the same manner as is the upper plate 1n the modification of Figs. 1, 2, l3 and 14.

A clockwise movement of the collar 34 will then urge the lower plate 39 forwardly. After the pin 36 passes beyond projection 42, the upper plate 40 is urged forwardly as in the modification of Figs. 1, 2, 13 and 14.

Only sliding movement is ermitted the upper and lower plates as t e pin 36 is guided in slots 35. Lateral movement of the lower and upper plates is prevented by the sides of the hand grip 33. In this respect, the operation of the two modifications is the same.

Heretofore switches employed in vacuum cleaners have been of the single-break type and an occasional short circuit of the break contacts energized the motor circuit. In both modifications of my invention the switch is of the double-break type discon necting the motor terminals from the line. Consequently, a short circuit on one set of cont-act members does not energize the motor circuit. As is apparent from Fig. 15, short lit) pactly arranged and the contacts and conductors are completely insulated, substantially all parts being housed in the handle and handle grip. The switch parts are few and simple in construction, and both upper and lower plates may be conveniently stamped. The push button 27 and the collar 34 are positioned conveniently for operation by one using the vacuum cleaner and grasping the hand grip.

The embodiments disclosed may be changed and modified Without departing from the spirit of the invention and a substantial range of equivalents is contemplated within the scope of the appended claims.

I claim as m invention:

, 1. The comb nation of a handle for a portable electrical device, a spring, a pair of conductors, a pair of members engaging said spring and slidable with respect to each other and said handle, means on one of said members for connecting said conductors electrically and means for moving said members relatively to each other to compress said spring and to release said spring w ereb the first-mentioned means is moved dlsconnect said conductors,

2. In a handle for a vacuum cleaner, the combination of a plurality of contact members and co-operating bridging members, a plurality of plates adapted to form a cup, a helical sprln housed in said cup, and manually opera 1e means for moving one of said plates with respect to another of said plates and simultaneously preventing movement of the first-mentioned plate whereby said spring is compressed, said manually ermitting the release of operable means said spring and t e movement of said firstmentioned plate after a predetermined degree of actuation is reached.

In testimony whereof, I have hereunto subscribed myname this 9th day of July, 1924.

CHRISTIAN ALALBORG. 

